Ok, looks aren't everything when it comes to mobile phones. But there's no denying that Apple's newly-launched iPhone 4 is a very nice piece of eye candy. But has Apple upgraded the inner workings sufficiently to tempt us in once more? Quite possibly.The new iPhone doesn't represent a 'game change' like the original iPhone, but it does offer evolution from the previous model, most notably in its styling. The new iPhone is crafted in stainless steel, with a glass touchscreen display. And at 9.3mm thick, it's also considerably slimmer than the previous model, 24 per cent thinner if you want the numbers. Steve Jobs related it to a vintage Leica camera, calling it 'one of the most beautiful designs you've ever seen,' which gives you an idea of how Apple might market this in the coming months. The antenna is also interwoven into the casing, which should improve network reception.All very nice, but what about the features? Well, iPhone 4 now uses Apple's own A4 chip and a micro-sim (like the iPad), with noise cancelling technology also included courtesy of two microphones. Connectivity is the usual 3G, Wi-Fi and Bluetooth, as you would expect.But things start to get interesting when we get to the screen. We're talking a 3.5-inch display at 960 x 640 resolution, considerably up on the 3GS. There's also a much improved 800:1 contrast ratio and Retina Display technology, the latter offering screen text as clear as reading a book (326dpi). Just as well, with Apple also introducing its book store for the iPhone, if your eyes are up to it.Imagery is much improved too. In comes a 5-megapixel camera with LED flash, which also offers the ability to shoot movies in 720p HD. There's even on-board editing and the option to buy iMovie for the iPhone, should you want to create a mini masterpiece. On the front is another camera, this time for what Apple is calling Face Time calling. Ok, it's just video calling - and only to other iPhone 4 users over Wi-Fi initially. But it certainly looks impressive and could mark video calling's entry into the mainstream.Finally, the new models will have the same storage capacities and a larger battery (working with that new chip to increase battery life further). All of which should hit the shelves of the chosen networks on June 24th 2010.